1. Field
Embodiments of the invention relate to electronic devices, and more particularly, in one or more embodiments, to data transmission for electronic devices.
2. Description of the Related Technology
Many electronic systems transmit data over a channel between devices. Referring to FIG. 1A, a conventional electronic communication system for transmitting a signal via a channel will be described below. The illustrated system 100 includes a transmitter device 110, a receiver device 120, and a channel 130.
The transmitter device 110 transmits data and/or control signals to the receiver device 120 via the channel 130. Examples of the transmitter device 110 include, but are not limited to, a video data source, an audio data source, or an audiovisual data source. For example, the audiovisual data source can be a DVD player.
The receiver device 120 receives data and/or control signals from the transmitter device 110 via the channel 130. Examples of the receiver device 120 include, but are not limited to, a display device, such as a television or monitor. The receiver device 120 can include a receiver 125 to receive and process data and/or control signals from the transmitter device 110.
The channel 130 can include one or more media, such as, but not limited to, copper twisted pair channels, printed circuit board traces, or optical fiber. In another example, at least part of the channel 130 can be wireless. In other examples, the system 100 can also include a “back-channel” between the transmitter device 110 and the receiver device 120. The back-channel can be used for exchanging, for example, control information. For example, the back-channel can be used to set pre-emphasis (transmit equalization) in the transmitter device 110. The transmitter device 110 can send a test pattern to the receiver device 120 so that the receiver device 120 can adapt the equalization gain of the receiver 125. If the equalization is at its maximum and there still exist bit errors above an acceptable rate, the receiver device 120 can inform the transmitter device 110 of this fact so that the transmitter device 110 can start pre-emphasizing its output in steps, and at each step the receiver device 120 can inform the transmitter device 110 of a bit error rate.
Referring to FIG. 1B, one example of the receiver 125 of FIG. 1A will be described below. The receiver 125 can be, for example, a High-Definition Multimedia Interface (HDMI) receiver. The illustrated receiver 125 is a 4-input receiver that includes first to fourth equalizers 130a-130d, first to fourth samplers 140a-140d, a multiplexer 150, and a processor 160. In other examples, the number of inputs of a receiver can vary widely (for example, 1 to 5 inputs).
Each of the equalizers 130a-130d receives three signals via the channel 130 (FIG. 1A) at inputs RXA—0 to RXA—2, RXB—0 to RXB—2, RXC—0 to RXC—2, RXD—0 to RXD—2, and processes the signals. Each of the samplers 140a-140c receives processed data signals from a respective one of the equalizers 130a-130d, and samples the signals. The multiplexer 150 receives the sampled signals from the samplers 140a-140d, and selectively or alternately provides the sampled signals to the processor 160. The processor 160 can process the sampled signals for, for example, playback at the receiver device 120 (FIG. 1A).
In one example, the electronic system 100 of FIG. 1A can form a serial digital link system in which the transmitter device 110 sends one or more streams of bits or digits encoded in suitable symbols to the receiver device 120 through the channel 130. In such an example, it is desirable that the serial link can transmit symbols at a given rate with low error probability.